Apparatus for internal truing of holes



R. LANGEL March 20, 1951 APPARATUS FOR INTERNAL TRUING OF HOLES 2 Sheets-Sheet 1 Filed Oct. 25, 1947 March 20, 1951 I R, LANGEL 2,545,435

APPARATUS FOR INTERNAL TRUING OF HOLES Filed Oct. 25, 1947 2 Sheets-Sheet 2 e 405 'a wzi 40 I w W. I i I r' Patented Mar. 20, 1951 APPARATUS FOR INTERNAL TRUING OF HOLES Robert Langel, Courtelary, Switzerland Application October 25, 1947, Serial No. 782,116 In Switzerland August 8,, 1941 Section 1, Public Law 690, August 8, 1946 Patent expires August 8, 1961 7 Claims.

The present invention relates to apparatus and more, particularly to apparatus for use in internal truing of holes which have been previously bored into a work piece.

According to an important feature of the invention, the apparatus comprises a block made of two parts within one. of which there is arranged a plunger lodged in a bushing, this plunger being provided with a recess for use as an oil chamber adapted for lubrication of the truing tools and of the frictionally engaging surfaces of the movable parts of the apparatus, and means being provided for delivering oil into the said chamber and feeding it from this chamber to the said tools and movable parts.

Such an improved apparatus may be useful for instance in. internal truing of holes which have, been previously bored in watch plates or bridges, or in pieces of electric apparatuses or the like, and in a general way in pieces which are intended to be interchangeable.

The accompanying drawings represent, by way of examples, two practical embodiments of the invention. In the drawings:

Fig. 1 is a vertical sectional view of a first apparatus embodying the invention;

Fig. 2 shows a horizontal cross-sectional view thereof along the line (1-1) of Fig. 1.;

Fig. 3 is a vertical sectional view of a second apparatus embodying the invention, and

Fig. 4 shows a horizontal cross-sectional view taken along the line cd of Fig. 3.

The apparatus for internal truing of holes shown in the Figures 1 and 2 comprises a block made of two distinct parts, namely: a stationary lower block part I and a movable upper block part 2, both parts being connected with one another by means of two guiding posts 3 and 4 the lower ends of which are secured in vertical holes provided in the body of the stationary lower block part I. This stationary. lower block part I is secured to the table of a press (not shown) and the movable upper block part 2 is slidingly mounted on the guiding posts 3 and 4 and is dependent upon the reciprocating movements of the said press. A plunger 5 is arranged within the stationary lower block part I and secured by its base to said block part by means of screws 6. The

plunger 5 is axially bored through its whole length and carries on its upper part a tool supporting plate 1 covering the upper end of the plunger bore and to which is fastened a tool holding plate 8 adapted to hold the truing tools 9 in correct working position. The plates 1 and 8 are Secured to the'plunger '5 by means of screws III.

The plunger 5 is lodged in and in sliding engagement with a bushing I I which in turn is slidingly mounted within a cylindrical recess provided in the lower block part I, between the wall of this recess and the body of the plunger 5. This bushing I I carries at its upper extremity a plate I2v carryingin turn a second plate It; both these plates are secured to the bushing I I by means of screws I4 and constitute the bottom wall of this bushing.

In order to lubricate the above described plunger and bushing assembly aswell as the tools held by the plates I and 8, the post 4 is provided with an axial channel I5 for the supply of the lubricating oil. From this channel I5, the oil is fed through a duct I6 and underneath the edge of the bushing II when the latter is in its upper position, as shown in Fig. l. The oil is then delivered into the axial bore I I of the plunger 5 intended as an oil chamber through inlet holes I8 provided in the lower part of plunger body. Two 7 uiding pins I9 are intended to prevent rotation of the bushing I I with respect tothe plunger 5. From the'oil chamber II, the oil is then fed throughholes 20 provided in the plates I and 8 into a hollow space 2! situated between the plates 8- and I2 to be further delivered to the tools and to the frictionally engaging surfaces of the plunger and of the bushing, when a pressure is exerted upon the bushing II, by the work piece (not shown) which is suitably positioned and removably fastened to the bolster of the movable upper block part 2.

In order to enable checking of the oil level in the channel I5,.this channel is provided with a float F as shown in the Fig. l,

The apparatus which is shown in Figures 3 and 4 comprises also a. block made of two distinct parts IllI and H12, but the plunger I and the corresponding bushing III are lodged in a recess provided in the movable upper part IE2 of the block. The upper block part I62 is slidingly mounted on two posts I03 and I04 extending vertically from the lower block part IOI to which they are secured. The plunger I05 is provided with an oil chamber I I1 and is secured by means of screws 22 to the movable upper part of the block. In the bushing III there are fixed screws 23 having av portion of their shank without threads and passing through holes provided in a flange of the plunger I05. These screws 23 are intended to limit the vertical movements of the bushing I II with respect to the plunger I05, while preventing angular displacement of the bushing with respect to the plunger. The bottom wall of 3 the bushing III is constituted by a single plate 24 secured to the cylindrical body of the bushing by means of screws H4. Reference numeral I60 designates the bolster of the stationary block part l! on which the work piece (not shown) should be suitably positioned and secured for the truing of holes which have been previously bored thereabout the periphery of the cross-bar 25 to be Supplied to the frictionally engaging surfaces of the bushing and of the plunger.

The operation of the apparatus for internal truing of holes which has been just described in connection with Figures 1 and 2 of the drawings is as follows:

When the movable part of the block carrying the work secured to the bolster 60 enters under actuation of the press in contact with the plate l3 of the bushing for truing holes previously bored in the work, the bushing is caused to slide downwardly on the plunger, thus pressing the oil which is comprised in the free space 2| situated between the plates 8 and I2 and urging it in part to the tools 9 and to the frictionally engaging surfaces of the bushing and of the plunger, whilst the remainder is delivered into the oil chamber ll. The truers 9 penetrate upwardly into the holes of the work and then into the corresponding holes of the bolster 6B. The truing tools 9 suitably formed with slightly tapered free end portions, are well covered with oil and in penetrating the holes of the work true them thoroughly.

In order to draw the bushing ll back into its initial position, there are provided pushers (not shown). The operation of the apparatus shown in Figures 3 and 4 only differs in that the truers penetrate downwardly into the holes of the Work.

The apparatus for internal truing of holes as described and shown in the drawings is intended to avoid formation of scum; owing tothe constant lubrication of the tools, the wear and tear of the latter will be practically reduced to zero. The tools will keep durably their cutting properties so that the waste of time for sharpening thereof will be reduced to a minimum extent. Owing to the cylindrical shape .of the main pieces of the apparatus shown in the drawings the said pieces will be subjected neither to decentering nor to accidental displacements during the working.

What I claim is:

1. An apparatus for internal truing of holes which have been previously bored into a work piece, comprising in combination a block made of two distinct parts one of which is stationary and the other movable, a cylindrical recess in one of those distinct parts, a bushing slidingly mounted in said cylindrical recess and having a bottom wall projecting from the outer surface of said recessed part facing the other block part, a plunger within said bushing in sliding engagement therewith and secured to said recessed block part, perforated plates holding said tool and secured to said plunger in spaced relation with said bottom wall of the bushing, said plates cover- ,ing'a recess in said plunger for use as an oil chamber for the oil destined to the lubrication of said tool and of the frictionally engaging surfaces of said bushing and plunger assembly, and means for delivering oil into said chamber and into the space between said tool holding plates and said bottom wall of the bushing, whereby upon actuation of said movable block part, oil is circulated by pressure exerted thereon by said bushing.

2. An apparatus for internal truing of holes of the character described as claimed in claim 1, wherein the bushing and plunger assembly is mounted in the stationary part of the block.

3. An apparatus for internal truing of holes of the character described as claimed in claim 1, wherein the bushing and plunger assembly is mounted in the movable part of the block.

4; An apparatus for internal truing of holes of the character described comprising in combination a lower stationary block part having two cylindrical holes to receive two vertical guiding posts, a movable upper block part slidingly mounted on said two vertical guiding posts, a cylindrical recess in said lower stationary part of the block to receive a bushing slidingly mounted therein, said bushing having an outer bottom wall adapted to be pressed downwardly by said movable upper block part, a plunger within said bushing in sliding engagement therewith and secured by its base to said lower block part, said plunger being cylindrically bored and carrying tool holding plates covering the upper end of its bore and spaced apart from the bottom wall of said bushing at least one tool supported by said tool holding plates, an oil channel in at least one of said vertical guiding posts, said channel communicating underneath said bushing with holes in the wall of said plunger, and holes passing through said tool holding plates merging into the free space comprised between said plates and the bottom wall of said bushing, whereby'oil may be fed upon actuation of said movable upper block part from said channel of the guiding post into said bore of the plunger and from said bore into saidspace between said tool holding plates and said bottom wall of the bushing for lubricating said tool and the frictionally engaging surfaces of said plunger and of said bushing.

5. An apparatus of the character described as claimed in claim 4', wherein the oil channel in the vertical guiding post is provided with a float for checking the level of the oil therein. .6. An apparatus of the character described as claimed in claim 4, wherein the bottom wall of the bushing is constituted by two superimposed plates having bores therein for guiding the tool held by the tool holding plates or" the plunger.

7. An apparatus for internal truing of holes of the character described comprising in combination a lower stationary block part having two vertical guiding posts secured thereto, a movable upper block part slidingly mounted on said vertical guiding posts, a cylindrical recess in said movable upper block part to' receive a bushing slidingly mounted thereimsaid bushing having an outer bottom wall adapted to be pressed upwardly by said stationary lower block part, a plunger within said bushing in sliding engagement therewith and secured by its base to said movable upper block part, said plunger being cylindrically bored and carrying tool holding plates covering the lower end of its bore and spaced apart from the bottom wall of said bushing at least one tool supported by said tool holding'plates, a cross bar having a central aperture covering the upper end of plunger'bore and secured to said plunger, an oil channel in the body of said movable upper 8 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,352,211 Kratzmaier June 27, 1944 FOREIGN PATENTS 10 Number Country Date 223,818 Switzerland Oct. 15, 1942 

